Compressed gas condenser



Aug. 18, 1959 A. KELLER COMPRESSED GAS CONDENSER Filed May 12, 1955 nitc d Sta e Pa COMPRESSED GAS CONDENSER Alexander Keller, Frankfurt am Main, Germany, assignor to Hartmann & Braun Aktiengesellschaft, Frankfurt amMain, Germany, a corporation of Germany Application May 12, 1955, Serial No. 507,938 Claims priority, application Germany June 29, 1954 3 Claims. (Cl. 317-244) The invention relates to condensers for high voltages. These condensers commonly are arranged in an insulating housing having the form of a cylindrical tube made of hard paper and gastight shut at the ends by a head plate and a base plate. The cylinder is filled with compressed gas, hence the name compressed gas condenser. The value of the voltage which causes external break-down depends in a very high degree upon the diameter of the hard paper tube. The larger the diameter the lesser is the maximum voltage gradient along the surface of the tube and the higher, therefore, is the voltage causing external breakdown-presumed the shape of the high tension electrode being maintained. It is desired to have an external break-down voltage of as high a value as possible. However, it is not possible to increase the diameter of the tube more and more since with increasing diameter of the tube the head-plate and base-plate must be enlarged too and thus also the force put on these plates by the compressed gas is increased. This force in the types known amounts to several tons; a further increase of the tube diameter would lead to uneconomic designs. Therefore it was only possible to build compressed gas condensers which are secured against external breakdown up to voltages of about one million volts.

It is the object of the invention to present a compressed gas condenser which does not show this limitation.

According to the invention the insulating housing of the condenser is convex-shaped in such a way that its distance from the electrodes reaches a maximum in that region where in the surroundings of the electrodes the voltage gradient has the highest value. This shape of the insulating housing permits to decrease the maximum volttage gradient on the surface of the insulating housing and consequently to increase the break-down voltage. In case there are also provided a head plate and a base plate the forces exerted upon them can be kept relatively small. By suitably shaping the insulating housing a practically constant voltage gradient along a generatrix of the insulating housing can be obtained. The insulating housing according to the invention advantageously is made of rubber or rubber-like material. This material besides its property of insulating and being gastight has the desired quality that it easily can be brought into the required shape and withstands even very high pressures. It is further feature of the compressed gas condenser according to the invention that in these condensers the length of the housing can be increased giving a further increase of the break-down voltage. in compressed gas condensers having a cylindrical hard paper housing an increase of the length has practically no influence upon the break-down voltage.

Compressed gas condensers according to the invention, therefore can be built for break-down voltages as high as is needed in practice.

The accompanying drawing shows by way of example a compressed gas condenser according to the invention in sectional view. Number 5 denotes the cylindrically shaped high voltage electrode. The high tension is led to it by conductor 10. In the inner of the high voltage electrode 5 there is arranged the low voltage electrode 8. It is carried by a grounded metal tube 9 and insulated against it. Conductor 11 extending through metal tube 9 leads to the low voltage electrode 8. The condenser formed by electrodes 5 and 8 is surrounded by a barrelshaped housing 1 consisting of stiffened rubber or rubberlike material. The edges at both the ends are bent to beaded edges 2 which by rings 3 are gastight drawn against respective headand base-plates 4. Because the housing ends are anchored and the housing is of rubberlike material the housing may be originally cylindrical, with the filling gas distending the housing mid-portion to form the mentioned barrel shape. Since the housing because of the high pressure acting on its inside cannot be regarded completely stiflf, there are provided traverses 6 secured to the headand base-plate and held at constant space by insulating posts 7. Thus the head-plate, along with the high tension electrode, is supported by means of the posts 7 in addition to the mere partial support by the rubber housing. Said insulating posts may consist of porcelain or they may be hard paper tubes and com-,

posed of several parts. Their length advantageously is chosen thus, that they are exposed only to small tensile or pressure load, i.e. nearly that value which equals the distance ofthe traverses in a free-standing condenser filled with compressed gas. Furthermore the insulating posts 7 serve for fixing the distance between both the electrodes 5 and 8 in order to avoid lateral or vertical deviation of the electrodes from their proper position and thus maintaining a defined capacity.

I claim:

1. High voltage condenser, comprising a tube of flexible material, a top and a bottom plate so that the flexible tube is gastight shut, two electrodes fixed at the inner face of the top and bottom plates, means for supporting said plates in order to maintain a definite position to each other, the case comprising the tube and top and bottom plates being filled with compressed gas so that the tube assumes a barrel shape, the diameter being largest in that range where near the electrodes the potential gradient is highest.

2. A high voltage condenser comprising a normally substantially cylindrical tube of yieldable flexible insulating material; substantially rigid closure members secured gastight on each of the respective ends of the tube; means for holding the closure members a fixed distance apart; a pair of electrodes within the tube and mounted fast with respect to the respective closure members and substantially coaxial with the tube, and a gas under pressure above that of the surrounding atmosphere within the tube to distend the mid portion of the tube to a greater than normal diameter to hold the mid portion away from the electrodes in the medial zone between the closure members.

3. In ahigh volfagecondenser, a normally substantially cylindrical-tube-of yieldable elastic insulating material; a pair of closure members of fixed dimensions mounted fast and gastight on the respective ends of the tube; means for holding the members a fixed distance apart; a pair of elongated electrodes in the tube, the maximum potential gradient due to the electrodes under load being in the medial Zone between ends of the tube, and a fluid under pressure within the tube for the double function of reducing arcing between the electrodes and distending the mid portion of the tube to hold the Walls thereof more remote from the electrodes in said zone than at the ends of the tube where the potential gradient is less.

References Cited in the file of this patent "UNiTED STATES IMTEN TS Lanchester Apr. 29, 1919 Kirch Aug. 11, 1936 'Floyd Nov. 16, 1948 Stacy Nov. 16, 1948 Longacre June 12, 1951 Suits Aug. 18, 1953 FOREIGN :PATENT S Great Britain Oct. 13, 1932 Great Britain June 20, 1946 

